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Jun 26, 2019 at 00:00
Playing with perf today! It's really interesting to see low-level details of where compute time is going. Branch prediction works well most of the time! (At least for this workload.) Based on https://jvns.ca/blog/2014/05/13/profiling-with-perf/ and
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I can spy on my CPU cycles with perf!
I can spy on my CPU cycles with perf!
Profiling in rust application
Profiling in rust application
As always in performance analysis, the answer depends on what exactly you want to know (for example, exact "number of calls to a function" is a very expensive quantity to measure, so most profilers prefer to give you an approximate "percent of time spent in the function" instead). But in my opinion, the best "default choice" these days is a hardware-assisted sampling profiler. These tools are either operating system or hardware-specific, here are some references that you can look up: Linux: p...

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